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Would Shvo's catalyst be suitable for reducing P2NP via catalytic transfer hydrogenation?
Urushibara is a ghost whining through the dusty chambers of chemistry, together with Akabori and some others he is elusive maybe even mythical . Unicorns have been seen more often then a working Urushibara thats all I know.
IIRC you can reduce the double bound of the Alkene with SnCl2/HCl in Ethyl Acetate in excellent yields to the Nitro-Alkane and THIS should be reduceable with noble metal catalysts without trouble.
Please regard the second one as an educated guess, I have to look it up to be sure. SnCl2 works 100% as told though.
Problem generally is that in the double bond reduction a Michael addition reaction on the intermediate is competing with the reduction, if conditions are neutral or alkaline.
You are right that the amounts of NaBH4 used in the CuSO4 reduction are a disgrace. There must be a way to reduce this.
I tried this reaction method for P2P to Amph several times as I was told it would give up to 80 % yields and I can tell you this apparently is utter bullshit and yields are ridiculously low. I am sure it will not work well on P2NP as alkaline conditions as told before a not favorable for the first step.Apparently you can do a Urushibara-like reduction in situ using a nickel salt dissolved in an ammonia solution and powdered zinc
SnCL2/HCl is defintely the way to go to produce the oxime according to the paper I read (since my last post) yields are very high and all reagents are readily available . I'm aware about ethyl acetate being the key otherwise you'll get the ketoxime but it seems the reaction itself proceeds at room temp and you can just stick a reflux condenser on the top and not have to babysit it like Al/Hg.
There's 2 of the same aldoxime to amine reduction papers in Rhodium's archive which seem to good to be true:
Again, easily available reagents (making ammonium formate is trivial) and high yields. If it works I wonder why this route doesn't seem to be popular. Even though its more labourious than Al/Hg it has some definite advantages.
SnCL2/HCl is defintely the way to go to produce the oxime according to the paper I read (since my last post) yields are very high and all reagents are readily available . I'm aware about ethyl acetate being the key otherwise you'll get the ketoxime but it seems the reaction itself proceeds at room temp and you can just stick a reflux condenser on the top and not have to babysit it like Al/Hg.
There's 2 of the same aldoxime to amine reduction papers in Rhodium's archive which seem to good to be true:
Again, easily available reagents (making ammonium formate is trivial) and high yields. If it works I wonder why this route doesn't seem to be popular. Even though its more labourious than Al/Hg it has some definite advantages.
SnCL2/HCl is defintely the way to go to produce the oxime according to the paper I read (since my last post) yields are very high and all reagents are readily available . I'm aware about ethyl acetate being the key otherwise you'll get the ketoxime but it seems the reaction itself proceeds at room temp and you can just stick a reflux condenser on the top and not have to babysit it like Al/Hg.
There's 2 of the same aldoxime to amine reduction papers in Rhodium's archive which seem to good to be true:
Again, easily available reagents (making ammonium formate is trivial) and high yields. If it works I wonder why this route doesn't seem to be popular. Even though its more labourious than Al/Hg it has some definite advantages.
Not shabby, 90%. I would suggest to prepare the SnCl2 beforehand as the in situ preparation is quite exothermic and easily leads to runaways as the onset of the SN - HCl reaction is delayed. If you want to do it in situ add a pinch of mercury salt what solves the problem of delayed reaction and makes it instantly. A pinch, a knifes tip suffices.The synthesis of 9-anthracenylacetaldoxime is representative. w-(Nitrovinyl)anthracene (1.25 g, 5 mmol), SnC12.2H20 (2.25 g, 10 mmol) and ethyl acetate (25 ml) were placed in a 50 ml Erlenmeyer flask and the mixture stirred at room temperature. A mildly exothermic reaction ensued which was accompanied by the gradual disappearance of the yellow coloration (nitroalkene). The reaction mixture was carefully poured into ice water and the solution made slightly basic (pH 7-8) by addition of 5% aqueous sodium bicarbonate. The product was extracted into ether, washed with brine, dried (Na2S04) and the solvent removed under reduced pressure to yield essentially pure E/Z mixture of 9-anthracenylacetaloxime, mp 177-18O'C; (1.05 g, 90%)
Kabalka, G. W., Laila, G. M. H., & Varma, R. S. (1990). Selected reductions of conjugated nitroalkenes. Tetrahedron, 46(21), 7443–7457. doi:10.1016/s0040-4020(01)89059-1
Kabalka and his team are first class reliable.
Not shabby, 90%. I would suggest to prepare the SnCl2 beforehand as the in situ preparation is quite exothermic and easily leads to runaways as the onset of the SN - HCl reaction is delayed. If you want to do it in situ add a pinch of mercury salt what solves the problem of delayed reaction and makes it instantly. A pinch, a knifes tip suffices.
Why those Indian nonsense articles? No, they are not SO stupid. It is about patent laws. In India one cannot patent a compound only its synthesis. Of course western Pharmacompanies file patents in India which try to cover ALL existing and a few non-existing ways to make the new drug. So sometimes Indians are barred from making a generic just for they have no own synthesis they can say they use. And so they built themselves an arsenal of unheard of, simple synths for basic stuff which is good enough for a patent. In the factory they use the best way to do it of course. And thats why one must be REALLY careful with Indian and Malayian Articles in special.
I'm purchasing the SnCl2 rather than making it (98% purity)
Yep, it's the same 2 Indians responsible for all the papers claiming Zinc/Ammonium formate can selectively reduce aldoximes. They're also responsible for claiming the same of Mg. There's papers not involving K. Abiraj and D. Gowda where azo compounds are reduced and one where imine was reduced to the secondary amine. Nothing that interests me currently. I was going to electroreduce the p2np all the way to the amine but I'll start with the oxime since it's an intermediate anyway. Can also form the imine I think by changing the ph.
Zn-Ni seems to work on p2p-oxime but the yields are garbage. I do have almost 1kg of p2p glycidic ester sitting around doing nothing though.
P2P-Oxime is the problem. The reduction of the Oxime can be done by Al/Hg or NaBH4/Cu or those Copper/iron oxide nanos quite nicely. And with several variations of sodium metal reduction.
But on topic, we started with P2NP reduction here yes?
I was returning to Zn-Ni (that french patent) since we were talking about it before the ammonium formate tangent. I didn't mean p2p oxime I've just been typing oxime far too many times today. I had a good look through forum archives and theres a few saying it worked on p2np, you said it won't. I said I was going to try it but now I've concluded I'll save it for the P2P.
On a separate note: I can't send you 50g because I don't have 50g (this is all hobby/personal use) I can send you 10g but I'm not in the EU
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